Injection valves are in widespread use, in particular for internal combustion engines where they may be arranged in order to dose the fluid into an intake manifold of the internal combustion engine or directly into the combustion chamber of a cylinder of the internal combustion engine.
Injection valves are manufactured in various forms in order to satisfy the various needs for the various combustion engines. Therefore, for example, their length, diameter as well as various elements of the injection valve which are responsible for the way the fluid is dosed may vary within a wide range. In addition to that, injection valves may accommodate an actuator for actuating a valve needle of the injection valve, which may, for example, be an electromagnetic actuator.
In order to enhance the combustion process with regard to the reduction of unwanted emissions, the respective injection valve may be suited to dose fluids under very high pressures. The pressures may be, in the case of a gasoline engine for example, in the range of up to 400 bar, and in the case of diesel engines in the range of up to 3500 bar.
WO 2005/080786 A1 describes a contact connection for contacting a valve needle of an internal combustion engine. The valve needle is guided in its upper part in a needle guide, which is a one-pieced component integrated within a valve body, isolated from its surroundings.
U.S. Pat. No. 5,299,346 describes an apparatus to align, burnish and secure an upper needle guide for a fuel injector valve body. The apparatus includes a lower portion having a fixture containing a spring-loaded plunger and a spring-loaded centering pin, and an upper portion having a burnishing tool, a spring-loaded stripper, and a crimping ram. The fixture aligns the needle guide and the valve body, and as the two portions are operated closed, the inside diameter of the upper needle guide is first burnished, and then the valve body is crimped onto the needle guide. The stripper holds the crimped parts against the lower portion of the apparatus while the upper and lower portions are operated open to withdraw the burnishing tool from the inside diameter of the needle guide.
EP 1 170 502 A1 describes an injector for injecting fuel into combustion chambers of internal combustion engines, comprising a control part protruding into a control space. The control part is guided in a guide sleeve surrounding the control space. The guide sleeve loaded by a spring element lies on a housing wall of the injector. The guide sleeve is centered on the first diameter region of the control part.